Thread: PID Control
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Unread 23-01-2013, 08:37
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Sparks333 Sparks333 is offline
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AKA: Dane B.
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Re: PID Control

To echo the current sentiment in the thread...

PID may help you, but there are easier ways to fix this.

First - the jerking. Do you have multi-motor gearboxes on the drivetrain? If so, calibrate your motor controllers - nothing messes with fine control as much as having two motors trying to do different things when geared together.

Next - try a drive curve. Implement a deadzone so the robot doesn't try to move when the speed controllers aren't on enough to move it, and map the joystick inputs so that closer in the robot will try to move less, and ramps up quickly to maximum at the extremes.

Lastly - beware braking. Depending on your gear ratio, setting braking in the speed controller can either make you stop quickly and be hard to push, or can make you stop immediately when input isn't given and cause the robot to move in a jerky fashion when the sticks move through the zero position.

Luck,

Sparks
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